Multiscale modeling and simulation of single-crystal MgO through an atomistic field theory

The present work is concerned with the application of an atomistic-continuum field theory (AFT) in modeling and simulation of crystalline materials. Atomistic formulation of the field theory and its finite element implementation are introduced. Single-crystal MgO under mechanical loading is modeled and simulated. With a coarse mesh, the field theory is shown to be able to simulate dynamic and nonlinear behavior of multi-atom crystalline materials without the need of additional numerical treatments. Reducing the finite element mesh to the atomic scale, i.e., the finite element size is equal to the size of the primitive unit cell, atomic-scale critical phenomena, including dislocations nucleation and motion, have been successfully reproduced.